Because they fix carbon dioxide differently, C4plants (they include maize, sorghum, millet and sugarcane) are around 50% more efficient than C3plants (such as rice, soybean, wheat, rye, oats, millet, barley, potato...). Despite accounting for just 3% of plant species, C4plants contribute 30% to terrestrial productivity. Assessing the presence or absence of 16 traits known to be important for the C4pathway in 73 different plants and using Bayesian modelling techniques, the scientists have shown that there is significant flexibility in the evolutionary paths that plants have used to get from C3to C4photosynthesis. This finding therefore implies that the engineering effort meant to develop more productive and efficient C3crops is not constrained to only one route.
(University of Cambridge, 09/10/2013)